Switch having magnetic latching means

ABSTRACT

A rotary switch with separable stationary and movable contacts and having a shaft which is rotatable to actuate the movement of the movable contacts between first and second operating positions. A spring return mechanism biases the shaft toward a first angular position corresponding to the first operating position of the movable contacts. A lever arm is mounted on the shaft for movement therewith and carries a magnetic armature. A stationary magnetic structure is disposed adjacent to the shaft and includes a permanent magnet member. When the shaft is rotated to a second angular position which corresponds to the second operating position, the magnetic armature engages or seats against the stationary magnetic structure and the magnetic flux from the permanent magnet member passes through the armature to magnetically latch the shaft in the second angular position against the influence of the spring return mechanism. An electromagnetic coil or winding is disposed on the stationary magnetic structure and is energizable to provide a magnetic flux which opposes the magnetic flux which passes through the armature from the permanent magnet member to thereby release the armature and the shaft which is then actuated to the first angular position by the spring return mechanism.

United States Patent [72] Inventors Charles M. Cleaveland Monroeville;Wesley L. McKeithan, Pittsburgh, both of, Pa. [21] Appl. No. 862,427[22] Filed Sept. 30, 1969 [45] Patented June 15, 1971 [73] AssigneeWestinghouse Electric Corporation Pittsburgh, Pa.

[54] SWITCH HAVING MAGNETIC LATCIIING MEANS 9 Claims, 15 Drawing Figs.

[52] U.S.CI H 335/170, 200/11 [51] Int.Cl.... 1101b 9/20 [50] 335/114,170,174, 253, 254,136,125, 77, 200/11,1lA

[56] References Cited UNITED STATES PATENTS 3,109,906 11/1963 Abendroth335/170 3,206,564 9/1965 Hauser 200/11 (A) 3,229,052 1/1966 Si1vius....200/11 (A) 3,253,098 5/1966 Perry 335/170 3,444,490 5/1969 KrummeL...335/170 Primary [:xammen-Harold Broome Attorneys--A T Stratton andClement L McHale ABSTRACT: A rotary switch with separable stationary andmovable contacts and having a shaft which is rotatable to actuate themovement of the movable contacts between first and second operatingpositions A spring return mechanism biases the shaft toward a firstangular position corresponding to the first operating position of themovable contacts. A lever arm is mounted on the shaft for movementtherewith and carries a magnetic armature. A stationary magneticstructure is disposed adjacent to the shaft and includes a permanentmagnet member. When the shaft is rotated to a second angular positionwhich corresponds to the second operating position, the magneticarmature engages or seats against the stationary magnetic structure andthe magnetic flux from the permanent magnet member passes through thearmature to magnetically latch the shaft in the second angular positionagainst the influence of the spring return mechanism. An electromagneticcoil or winding is disposed on the stationary magnetic structure and isenergizable to provide a magnetic flux which opposes the magnetic fluxwhich passes through the armature from the permanent magnet member tothereby release the armature and the shaft which is then actuated to thefirst angular position by the spring return mechanism.

PATENTED JUN] 5:971

SHEET 1 [IF 2 FIGB.

aso INVENTORS WITNESSES Charles M. Cleovelond 0nd Wesley L, McKeithonATTORNEY SWITCH HAVING MAGNETIC LATCHINGMEANS BACKGROUND OF THEINVENTION This invention relates to rotary control switches and moreparticularly to means for remotely operating such switches.

In certain types of electrical apparatus such as rotary switches of thetype disclosed in U.S'. Pat. Nos. 3,206,564; 3,229,051; and 3,229,052which are all assigned to the same assignee as the present application,it is sometimes necessary or desirable to provide for operation of theswitches from a point or location which is remote from the switches. Forexample,'in a particular application, simultaneous operation of aplurality of rotary switches may be required to actuate the simultaneoustripping of a plurality of associated circuit breakers. In knownswitches of this type, one means for remote operation of such switcheswhich has been employed is to mechanically latch each switch in aparticular operating condition and to employ an electrical solenoidwhich is energized to actuate the release of the mechanical latch forremote operation of the associated switch. Such known switch structureshave certain disadvantages with respect to either the overall'sizeandweight of the switch structure or with respect to the speed ofoperation of the switch when operated from a point which is remote fromthe switch.

SUMMARY OF THE INVENTION In accordance. with the invention, a rotaryswitch comprises separable stationary and movable contacts whoseoperation between first and second operating positions is actuated bythe rotation of an associated shaft between corresponding first andsecond angular positions, respectively. A biasing means which may be ofthe spring return type, is provided to bias the shaft to the first ofthe angular operating positions of said shaft. A lever arm having amagnetic armature thereon is mounted on the shaft for rotationtherewith. A stationary magnetic structure is disposed adjacent to theshaft and includes a permanent magnet member. When the shaft is manuallyactuated to the second angular position by suitable means such as ahandle, the armature engages the stationary magnetic structure and themagnetic flux from the permanent magnetic member passes through thearmature to magnetically latch the shaft in the second angular positionagainst the influence or force of the associated biasing means. In orderto release the armature, an electromagnetic means, such as anenergizable winding, is disposed on the stationary magnetic structure toprovide a magnetic flux which opposes the magnetic flux which passesthrough the armature from the permanent magnet member thereby reducingthe holding or latching force of the stationary magnetic structure. Whenthe armature is released, the shaft is actuated to the first angularposition of said shaft by the biasing means.

In an illustrated embodiment of the invention, a second shaft having ahandle mounted thereon may be provided which is coupled to the shaftwhich actuates the operation of the overall switch contacts by acoupling means which couples the shafts together for rotation in adirection toward the second angular position of the shaft. This couplingmeans provides a predetermined amount of rotary lost motion between theshafts when the second shaft is rotated in a direction away from thesecond angular position of the other shaft to thereby restrict or limitcontrol of the switch to remote operation when the other shaft ismagnetically latched in the second angular position.

It is therefore an object of this invention to provide a new andimproved means for remotely operating a rotary switch structure.

BRIEF DESCRIPTION OF THE DRAWING Other objects of the invention will beapparent from the following detailed description taken in conjunctionwith the accompanying drawings, in which:

FIG. Us a view, partly in side elevation and partly in section, of arotary switch structure embodying the invention;

FIG. 2 is a view, in section, taken along the line II-II of FIG.

FIG. 3 is a view, in section, taken along the line III-III of FIG. 1;

FIG. 4 is a view, in section, taken along the line I\ /-IV of FIG. 1,with certain parts broken away;

FIG. 5 'is an enlarged diagrammatic view of a magnetic structure whichforms part of the switch structure shown in FIG. I;

FIG. 6 is an enlarged detail view showing a portion of the rotary switchof FIG. I;

FIG. 7 is a view, in section, taken along the line VII-VII of 7 FIG. 6;

FIGS. 8 and 9 are sectional views similar to FIG. 7 illustrating theparts shown in FIG. 7 in other operating positions;

FIG. 10 is an enlarged detailed view showing a modified portion of therotary switch of FIG. 1;

FIG. 11 is a view, in section, taken along the line XI-Xl of FIG. 10; 4

FIGS. I2 and 13 are sectional views similar to FIG. 11 illustrating thepositions of the parts in other operating positions;

FIG. 14 is a schematic diagram illustrating the electrical connectionsof certain portions of the rotary switch shown in FIG. I in a particularapplication; and

FIG. 15 is an enlarged detailed view showing a modified portion of therotary switch of FIG. 1;

DESCRIPTION ()F THE PREFERRED EMBODIMENTS Referring now to the drawingsand FIG. 1 in particular, the switch structure shown therein comprises adial plate assembly 222, a first housing 210 for a magnetic latchingmeans 30, a mechanism housing 153, a first stage stator housing 23, asecond stage stator housing 25, and the spacing members 27 which aredisposed at the opposite ends of the stator housings 23 and 25 and whichmay be disposed between successive stator housings where a plurality ofstator housings are provided as disclosed in greater detail in US. Pat.No. 3,206,564 and the other patents previously mentioned for a switchstructure of the same general type as shown in FIG. 1. A first shaft 26extends axially through most of the switch structure and is rotatablydisposed in bearings (not shown) which may be provided at one end of theswitch structure and at a location near the other end of the switchstructure. A second shaft 126 projects axially to the left of the dialplate assembly 222 and extends axially into the housing 210 with thesecond shaft 126 being coupled to the first shaft 26 by a coupling meanswhich includes the bushing 122 for rotation with the first shaft 26during certain operating conditions, as will be described hereinafter. Ahandle 28 is removably attached or secured to the left end of the secondshaft 126 by a screw 29 and an end cover (not shown) may be removablyattached at the other end of the switch structure opposite the handle28. A rotor assembly 20 and a cam 73 may be carried by the first shaft26 and where provided are rotatable with the shaft 26.

The switch structure shown in FIG. 1 may be mounted on a switchboardpanel 33 or other supporting structure by means of the screws 162 whichextend through the dial plate assembly 222 and the first housing 210 andinto the mechanism housing 153 which is disposed on the opposite side ofthe panel 33 from the dial plate assembly 222. The heads of the screw162 are covered by the dial plate cover 22 which is snapped over thedial plate assembly 222.

The stator housings 23 and 25 may be retained in axial alignment on theswitch structure by means of the bolts 183 which extend axially from themechanism housing 153 through the stator housings 23 and 25 and anyadditional stator housings where provided, as explained in detail in thepatents previously mentioned. The stator housings 23 and 25, the spacingmembers 27, the rotor 63 of the rotor assembly 20 and the cam 73 arepreferably molded from an electrically insulating material havingexcellent nontracking arc and wear resistant characteristics, such as aglass-polyester material with an aluminum trihydrate filler. Thus eachof the parts of the switch structure which are subject to wear has arelatively long life.

As indicated-in FIG. 1, a plurality of pairs of stationary contactmembers 47 may be disposed in two rows around the periphery of the firststator housing or contact support member 23. The respective pairs ofcontact members 47 are angularly or circumferentially spaced atpredetermined angles around the periphery of the switch structure. Thetwo contact members of each pair are spaced axially with respect-to thestator housing 23. Each contact member 47 functions as a terminal'member and as a contact member. Each contact member 47 is composed of asuitable electrically conducting material and may have a head which isenlarged in one plane to engage the walls of a recess in the statorhousing 23, as

described in detail in the patents previously mentioned. The

head of each contact member 47 may be beveled and is engaged by acontact roller carried by the rotor assembly 20, as will be describedmore fully hereinafter. Each contact member 47 is retained in the statorhousing 23 by means of a nut 49 which isthreaded onto the contact member47 to engage a washer, as shown in FIG. 1. The number of pairs ofcontact .members 47 and their relative positions may be varied asrequired in a particular application, as disclosed in detail in thepatents previously mentioned.

The rotor assembly may have one or more contact rollers 61 disposed atpredetermined angular positions around the periphery of the rotorassembly 20 as required in a particular application. The rotor assembly20 may be of a one-piece construction and comprises a hub 63 and aplurality of arms which are formed integrally with the hub 63, asdescribed in detail in the patents previously mentioned. Each contactroller 61 is composed of a suitable electrically conducting material andis provided with two spaced, integrally formed enlarged contact portions65. Each contact roller 61 is disposed in a slot provided in one of thearms of the rotor assembly 20 and is biased radially outwardly in therotor assembly 20 by an associated spring with aspn'ng seat 67 beingdisposed between one end of each'of the contact rollers 61 and theassociated spring. In

order to reduce the friction between the contact portions 65 of eachcontact roler 61 and the heads of the stationary contact member 47,'eachcontact roller61 is rotatably mounted in one of the arms of the rotorassembly 20 and in order to further reduce such friction, a wheel 69which is composed of electrically insulating material may be rotatablymounted on each end of each of, the contact rotors 61 outside of theadjacent enlarged contact portion 69, as described in detail in thepatents previously mentioned. In order that the rotor assembly 20 rotatewith the shaft 26, the hub 63 of the rotor assembly 20 has a squareopening for receiving the shaft 26 and the portion of the shaft 26 onwhich the rotor assembly 20 is carried has a similar cross section.

In certain applications, it is desirable to provide a switch structurehaving normally closed contact members. The second stator housing orcontact support member 25 shown in FIG. 1 has such normally closedcontact members mounted thereon. As indicated in FIG. 1, a plurality ofpairs of axially spaced contact members 57 may be angularly orcircumferentially spaced around the periphery of the stator housing 25with the inner ends 77 of each pair of contact members 57 extendingaxially toward each other. A bridging contact member 71 is biased intoengagement with the ends 77 of the associated contact members 57 by anassociated spring as described in detail in the patents previouslymentioned. The bridging contact member 71 is disengaged from the ends 77of the contact members 57 when a roller 75 on the bridging contactmember 71 is engaged by the cam 73 with the movement of the contactbridging member 71 being guided by a contact guide 79 which is disposedbetween the contact members 57 of each pair of contact members. The cam73 also includes a hub portion having a square opening for receivingshaft 26 with the portion of the shaft 26 which carries the cam 73having a similar cross section in order that the cam 73 rotates with theshaft 26. I

In order to return or bias the shaft 26 to a normal or off? angularoperating position as indicated at 228' in FIG. 8 which corresponds to afirst operating position of the movable contact rollers 65 and thebridging contact members 71, where provided, when the shaft 26 isreleased from the influence of the magnetic latching means 30, as willbe described more fully hereinafter, a spring return assembly ormechanism 50 is provided in the housing 153. As best shown in FIGS. 1and 4, a doubly wound spring 152 is disposed on a bushing 137 whichrotates with the shaft 26. The bushing 137 is provided with theprojections or ears 137A and 1378 which engage the ends of the spring152 and the ends of the spring 152 engage the projections or stops 143and 145 in the mechanism housing 153 to return the shaft 26 to itsnormal or "off" angular operating position when the shaft 26 isreleased. In order to reduce the friction between the spring 152 and thebushing 137, a generally tubular bushing 136 which is formed from amaterial having a relatively low coefficient of friction such as 0.17 isdisposed on the bushing 137 between the turns of the spring 152 and theouter surface of the bushing 137. It is to be noted that the housing 153may be closed off at the front end thereof by means of a cover plate 155having an opening through which the shaft 26 passes as shown in FIG. 1.

In order to magnetically latch the shaft 26 in a second angularoperating position or on" position which corresponds to a secondoperating position of the movable contact rollers 61 and the bridgingcontact members 71, where provided, a releasable magnetic latching meansor mechanism 30 is disposed in the first housing 210, as shown inFIG. 1. It is to be noted that the housing 210 may be secured to themechanism housing 153 by suitable means, such as a plurality of screws165, which pass through openings provided in the front of the housing210 and in a rear cover plate 212 and that a gasket 211 may be providedbetween the front portion of the housing 210 and the rear cover plate212 to prevent the entrance of dust or other contaminating materialsinto the housing 210.

More specifically, the magnetic latching means 30 as shown in FIGS. 1and 3 includes a lever arm 220 which is mounted on the shaft 26 forrotation therewith. The upper end of the lever arm 220 has a squareopening which is adapted to receive a portion of the shaft 26 having asimilar cross section or shape. In order to axially position the leverarm 220 on the shaft 26, the generally tubular spacer member 129 isdisposed on the shaft 26 between the lever arm 220 and the rear cover212 of the housing 210. A magnetic armature or movable keeper member 230is loosely mounted or supported at the outer end of the lever arm 220 bysuitable means, such as the screw 232.

The magnetic latching means 30 also includes a stationary magneticstructure 300, as shown in FIGS. 3 and 5. As shown in FIG. 5, thestationary magnetic structure 300 comprises a pair of spaced upper andlower plates 313 and 315, respectively, which are formed from a suitablesoft magnetic material, such as steel or iron. It is to be noted thatthe right ends of the plates 313 and 315 form the pole faces 316 and318, respectively, against which the armature 230 seats or engages whenthe lever arm 220 is magnetically latched by the magnetic latching means30, as will be described more fully hereinafter. In order to provide themagnetic flux which passes through the armature 230 and magneticallylatches the armature 230 against the stationary magnetic structure 300as shown in FIG. 5, a permanent magnet member 350 is provided whichextends traversely between the plates 313 and 315, as shown in FIG. 5.In order to provide an alternate path having a relatively low magneticreluctance for the magnetic flux from the permanent magnet member 350 tothereby prevent demagnetization of the permanent magnet member 350 andto reduce the amount of magnetic fiux provided by the coil 320 which isrequired to release the armature 230, the stationary magnetic structure300 also includes a magnetic plate member or fixed keeper 312 which isdisposed adjacent to the left ends of the plates 313 and 315 and whichis also formed from a suitable magnetic material, such as steel or iron.It is to be noted that the fixed keeper 312 is spaced from the adjacentends of the plates 313 and 315 by a spacer member 314 which is formedfrom a nonmagnetic material and which establishes a predeterminednonmagnetic gap in the altemate, low reluctance path which includes thefixed keeper 312.

In order to actuate the release of the armature 230 and, in turn, theshaft 26 when the armature 230 is magnetically latched to the stationarymagnetic structure 300 as shown in FIGS. 3 and 5, the energizing oroperating coil or winding 320 is disposed on one of the magnetic plates313 or 315. The

operating coil or winding 320 may include a plurality of conductor turnswhich are disposed to surround the upper mag-.

netic plate 313 as illustrated. When a voltage is applied to theoperating coil or winding 320 and current flows in the conductor turnsof the operating coil or winding, the magnetic flux which is producedwill be in such a direction as to pass through the armature 230 and tooppose the magnetic flux from the permanent magnet member 350 whichpasses through the armature 230. The effective reluctance of themagnetic path which includes the armature 230 will be thus increased andthe magnetic flux from the permanent magnet member 350 will then shiftor transfer to the relatively lower reluctance magnetic path whichincludes the fixed keeper312 to thereby release the armature 230 and theassociated shaft 26. It is to be noted that the various parts which formthe stationary magnetic structure 300 as just described may beencapsulated or embedded in a suitable thermosetting material,

such as an epoxy resin, or a thermoplastic resin and that the stationarymagnetic structure 300 may be secured to the rear cover 212 of thehousing 210 by suitable means, such'as a plurality of rivets 161, whichpass through the stationary magnetic structure 300 and secure thestationary magnetic structure 300 to the rear cover 212 of the housing210.

As previously mentioned, the shaft 126 on which the handle 28 is mountedis operatively connected or coupled to the shaft 26 during certainoperating conditions by a coupling means which comprises the generallytubular bushing member 122, as best shown in-FIGS. 1, 6 and 7. Morespecifically, the bushing 122 is secured to the shaft 126 for rotationtherewith by a cross pin 123 which passes through aligned openings inthe bushing 122 and the shaft 126. The bushing 122 also includes aportion 122A of reduced size which projects through an opening in thefront portion of the housing 210 to assist in rotatably supporting theshaft 126. The cross pin 123 may also include a portion which projectsbeyond the outer surface of the bushing 12.! and which is adapted toengage a stop member 223 which is formed, as illustrated, integrallywith the front portion of the housing 210, as best shown in FIGS. 1,2and 3. The bushing 122 also assists in axially positioning the lever arm220 on the shaft 26 since the right end of the bushing 122 as viewed inFIG. 1 projects over the adjacent end of the shaft 26 with the lever arm220 being disposed between the housing 122 and the spacer member 129.The shaft 126 also includes a portion 126A of reduced cross sectionwhich projects axially into a recess 26A which is provided at the leftend of the shaft 26 as viewed in FIG. 1 to assist in rotatablysupporting the shaft 126.

In order to provide a predetermined amount of rotary lost motion betweenthe shafts 126 and 26 when the handle 28 and the shaft 126 are rotatedin a direction that would rotate the shaft 26 and the associated leverarm 220 in a counterclockwise direction, as viewed in FIG. 3 and thatwould otherwise move the armature 230 away from the latched positionshown in FIGS. 3 and 5, the bushing 122 includes a plurality ofgenerally arcuate recesses 122C as best shown in FIG. 7. As shown inFIG. 7, the generally arcuate recesses 122C of the bushing 122 aredisposed adjacent to the corners of the square shaft 26 so that when thehandle 28 and the associated shaft 126 along with the bushing 122 arerotated in a counterclockwise direction, as viewed in FIG. 7, thebushing 122 will rotate in a counterclockwise direction to the positionshown in predetermined amount of rotary lost motion is provided betweenthe shafts 126 and 26 when the shaft 126 is rotated in t acounterclockwise direction from the position shown in FIG. 7, whichcorresponds to the position of the shaft 126 in FIG. 1, to the positionshown in FIG. 8 to thereby prevent the manual release of the lever arm220 under the influence of the force exerted on the handle 28 and theassociated shaft 126. In order to prevent the shaft 126 from beingrotated in a counterclockwise direction beyondthe limits of thepredetermined amount of rotary lost motion indicated in FIGS. 7 and 8,the cross pin 123 is extended radially as shown in FIG. 3 andengages thestop member 223 on the housing 210 to prevent the shafts 126 and 26 in acounterclockwise direction to thereby prevent manual overriding of themagnetic latch and also prevent the shaft 26 from being manually turnedto the off" position of the contacts.

On the other hand, if the shaft 126 is rotated manually by means of thehandle 128 in a clockwise direction, the internal configuration or shapeof the bushing 122, as shown in FIG. 7, is such as to cause the shaft 26to rotate with the shaft 126' in a direction to actuate the lever arm220 and the armature 230 toward the latched position shown in FIG. 3from the normal or off" position of the shaft 26 which is indicated bythe dotdash line 228' in FIG. 3.

In order to apply a unidirectional voltage to the operating coil orwinding 320 of the stationary magnetic structure 300, as shownschematically in FIG. 14, a source of alternating current voltage asindicated at S1 may be electrically connected to the operating coil 320through the contact 410 of the relay 400 which actuates the remoteoperation of the switching structure shown in FIG. 1, the closed contactrollers 61 of the switch structure previously described, the terminalsof a terminal block indicated diagrammatically at 360 in FIG. 14, andthrough the full wave rectifier 340, which is indicated in block form inFIG. 14. The rectifier 340 may be omitted with an alternating currentsupply if maximum speed of the switching operation is not necessary. Inother words, the coil 320 will function properly when energized witheither direct current or alternating current power. Minimum operatingtime is assured by direct current since alternating current may producemagnetic flux during the half-cycle which is in a direction to aid theflux from the permanent magnet member 350 rather than oppose it.

In order that the position of the handle 28 reflect the actual operatingcondition of the switch structure shown in FIG. 1, a pair of biasingleaf springs 255 are disposed to engage the shaft 126, as best shown inFIG. 2. The bent ends of the leaf springs 255 are disposed in thearcuate recesses provided in .the dial plate 222, as indicated at 222Aand 2228. When the handle 28 and the associated shaft 126 are rotated ina counterclockwise direction while the switch structure is magneticallylatched by the magnetic latching means 30 previously described, thehandle 28 and the shaft-126, along with the bushing 122, may rotate in acounterclockwise direction to the positions indicated in FIG. 8 withoutunlatching the armature 230 and the shaft 26, as just explained. Whenthe handle 28 is then released, the leaf springs 255 will actuate thehandle 28 to the position indicated in phantom at 228 in FIG. 2 in orderthat the handle 28 reflect the actual operating condition or position ofthe switch structure shown in FIG. 1. When the shaft 26 is releasedbythe energization of the operating coil or winding 320, the bushing 122and the shaft 26 will be actuated from the position shown in FIG. 7which corresponds to the magnetically latched condition of the switchstructure shown in FIG. 1 in a counterclockwise direction to theposition shown in FIG. 9 due to the internal configuration of thebushing 122, as indicated in FIGS. 7 and 9, and the handle 28, alongwith the shaft 126, will be actuated in a counterclockwise directionagainst the influence exerted on the shaft 126 by the biasing springs255 since the spring return mechanism which includes the spring 152 isrelatively stronger than the leaf springs 255.

In the overall operation of the switch structure shown in FIG. 1, itwill be assumed first that the switch structure is in the off" or normalcondition which corresponds to the first angular position of the shaftshown in FIG. 9 and which is indicated by the dot-dash line 228' in FIG.3. In this operating condition, the armature 230 and the lever arm 220are spaced away from the associated stationary magnetic structure, asindicated by the dot-dash line 228' in FIG. 3. In order to actuate thearmature 230 to the magnetically latched position shown in FIG. 3, thehandle 28 and the associated shaft 126, along with the bushing 122, arerotated in a clockwise direction, as viewed in FIG. 9, and due to theinternal configuration of the bushing 122 as indicated in FIGS. 7through 9, the shaft 26 will rotate with the shaft 126 until the shaft26 reaches the second angular position shown in FIG. 7 and the armature230, as well as the lever arm 220, reach the operating positions shownin FIG. 3 with the magnetic flux from the permanent magnet member 350passing through the armature 230 which engages the pole faces 316 and318 of the stationary magnetic structure 300, as previously described.It is to be noted that in this operating condition of the switchstructure, the reluctance of the magnetic path which includes thearmature 230 is relatively lower than that of the magnetic path whichincludes the fixed keeper 312 due to the presence of the nonmagneticspacer member 314 and that most of the magnetic flux from the permanentmagnet member 350 will therefore pass through the armature 230 tomagnetically latch the armature 230 to the stationary magnetic structure300.

Assuming that the armature 230 is in the magnetically latched positionshown in FIGS. 3 and 5 and that the shaft 26 is in the "on" operatingposition indicated at 228 in FIG. 7, if the handle 28 and the shaft 126,as well as the bushing 122, are rotated in a counterclockwise directionfrom the operating positions shown in FIGS. 3 and 7, the predeterminedamount of rotary lost motion between the shafts 126 and 26 will permitthe bushing'122 to rotate to the position shown in FIG. 8 withoutunlatching the armature 230. This is due to the predetermined amount ofrotary lost motion which is provided between the shafts 126 and 26, aspreviously described.

Assuming that the switch structure shown in FIG. 1 is in themagnetically latched condition and that the shaft 26 is in the positionshown in FIG. 7, the switch structure shown in FIG. 1 may be remotelyoperated by energizing the operating coil or winding 320 of thestationary magnetic structure 300 shown in FIG. 5 by energizing saidoperating coil from a source of alternating current, as indicated at S1in FIG. 14, through the full wave rectifier 340, as indicated in FIG.14, by the closing of a contact 410 of a suitable control relay, asindicated at 400 in FIG. 14, or from a source of direct current ifprovided. It is to be noted that prior to the energization of theoperating coil 320, the force exerted on the shaft 26 by the magneticlatching means 30 through the lever arm 220 is relatively greater thanthe force exerted on the shaft 26 by the spring return mechanism 50.When the operating coil 320 of the stationary magnetic structure 300 isenergized, the magnetic flux from the operating coil 320 will passthrough the armature 230 in such a direction as to oppose the magneticflux from the permanent magnet member 350 to thereby release thearmature 230 and the shaft 26 which will then move in a counterclockwisedirection from the position shown in FIG. 7 to the position shown inFIG. 9 which corresponds to the second operating position of the switchstructure shown in FIG. I. When the shaft 26 is actuated from theposition shown in FIG. 7 to the position shown in FIG. 9 under theinfluence of the spring return mechanism 50 which includes the spring152, the contacts 61 indicated diagrammatically in FIG. 14 will beactuated to the open position to thereby deenergize the operating coilor winding 320 of the stationary magnetic structure 300, so that it isnot necessary to have a continuous current flowing in the winding 320.

It is to be noted that in the overall operation of the switch structureshown in FIG. 1 as just described, the loose mounting of the armature230 on the lever arm 220 facilitates the alignment of the armature 230,the seating of the armature 230 on the pole faces 316 and 318 of thestationary magnetic structure 300 when the lever arm 220 is actuated tothe magnetically latched position shown in FIG. 3.

Referring now to FIGS. 10 through 13, there is illustrated a secondembodiment of the invention which comprises a switch structure aspreviously described except that the shape of the shaft 26 is modifiedto a shape as indicated by the shaft 326 in FIGS. 11 through 13 and theconstruction of the bushing 122 is modified to a shape as indicated bythe bushing 322 in FIGS. 11 through 13. More specifically, the bushing322 as indicated in FIGS. 11 through 13 is secured to the shaft 126 andincludes a square openingas indicated at 322A. The shaft 326 whichcorresponds to the shaft 26 of the switch structure previously describedis generally square except that the corners of the shaft 326 are groundoff as indicated in FIGS. 11 through 13.

The overall operation of the switch embodiment indicated in FIGS. 10through 13, is the same as the operation of the switch structurepreviously described. Briefly, when the handle of the switch which ismounted on the shaft 126 is rotated in a counterclockwise direction fromthe position indicated in FIG. 11 when the switch structure is in themagnetically latched position which corresponds to the angular operatingposition of the shaft 326 shown in FIG. 11, the bushing 322 will rotatein a counterclockwise direction to the position shown in FIG. 12. Theconstruction of the shaft 326 and the bushing will provide apredetermined amount of rotary lost motion between the shafts 126 and326 similar to the construction shown in FIGS. 6 through 9. In otherwords, when the switch structure of the second embodiment is in themagnetically latched condition indicated by the angular position of theshaft 326 in FIG. 11 and the handle on the shaft 126 is rotated in thecounterclockwise direction along with the bushing 322, the bushing 322will rotate in a counterclockwise direction to the position indicated inFIG. 12 without actuating the release of the magnetic armature on theshaft 326, as indicated in FIGS. 11 and 12. When the handle on the shaft126 is actuated in the counterclockwise direction along with the bushing322 from the position indicated in FIG. 11 to the position 12 and isthen released, the handle on the shaft 126 will be returned to theposition indicated at 228, FIG. 11 by the biasing leaf springs 255, aspreviously described in connection with the switch structureshown inFIG. 1. When the operating coil or winding 230 of the switch embodimentindicated in FIGS. 10 through 13 is energized and the shaft 326 isreleased from the magnetically latched position shown in FIG. 11, theassociated spring return mechanism 50 will actuate the shaft 326 in acounterclockwise direction from the position shown in FIG. 11 to theposition shown in FIG. 13 to thereby also actuate the bushing 322 in acounterclockwise direction due to the configuration of the shaft 326 andthe bushing 322.

Assuming that the switch embodiment indicated in FIGS. 10 through 13 isin the normal or off position as indicated by the angular position ofthe shaft 326 in FIG. 13, the switch structure may be actuated manuallyto the magnetically latched position by rotating the handle on the shaft126 in a clockwise direction, as viewed in FIG. 13, and the shafts 126and 326 will then rotate together in a clockwise direction from theposition of the shaft 326 indicated in FIG. 13 to the position indicatedin FIG. 11 which corresponds to the magnetically latched position of theshaft 326. In summary, the switch embodiment indicated in FIGS. 10through 13 is the same as the construction of the switch structure shownin FIG. 1 except that the configuration of the bushing differs from thatof the bushing 122 and the shape of the shaft 326 differs from the shapeof the shaft 26 as previously described. Both embodiments provide apredetermined amount of rotary lost motion between the correspondingshafts in one direction of rotation and with the shafts rotatingtogether in the opposite direction of rotation toward the magneticallylatched position of the shafts which form part of the overall switchstructures.

Referring now to FIG. 15, there is illustrated a third embodiment of theinvention which comprises a switch structure as previously describedexcept that the shaft 26' is extended forward from the rear portion ofthe switch parts to support the handle 28' and comprises the only shaftof this switch embodiment. The handle 28' is modified to include aninternal opening of the same configuration as the internal opening .inthe coupling 122 shown in H68. 7 through 9 to thereby provide apredetermined amount of rotary lost motion between the handle 28 and theshaft 26', which is rectangular in cross section, for a direction ofrotation of the shaft 26' away from the ngular position of the shaft 26'which corresponds to the magnetically latched position of the lever armand the armature which are mounted on the shaft 26' for rotationtherewith. The handle 28 is retained axially on the shaft 26 by a screw29" having an enlarged portion 29A which is not threaded and forms ashoulder which bears against the end of the shaft 26' when the innerthreaded end of the screw 29 is screwed into a threaded openingprovidedin the end of the shaft 26'. The screw 29' therefore permits limitedrotary rotation of the handle 28 on the shaft 26' in accordance with therotary lost motion provided. Otherwise the structure and operation of.the switch embodiment shown in FIG. 15 is the same a for the switchembodiments previously described.

it is to be understood that in certain applications the switchembodiments previously described may be constructed to permit the manualactuation of the switch structure from the magnetically latchedcondition to the normal or off operating condition by eliminating thepredetermined amount of rotary lost motion between the respective shaftsas provided in the switch construction described by mounting theoperating handle directly on the shaft which is magnetically latched bythe latching means in the different switch embodiments described or bycoupling the shaft on which the handle is mounted'to the shaft which ismagnetically latched in the different switch embodiments described by acoupling means, such as the coupling 322, which does not provide anyrotary lost motion. In other words, the handle 28 in one such modifiedconstruction may be mounted directly on the shaft 26 in the first switchstructure described and directly on the shaft 326 in the second switchembodiment described.

The apparatus embodying the teachings of this invention has severaladvantages. For example, a rotary switch structure as disclosed has beenfound to permit a relatively smaller size and weight than known switchstructures of the same general type. The size of such switches isparticularly important when the switches are to be mounted on a controlpanel or switchboard panel along with a plurality of similar switchesand other components. The second important advantage of the disclosedswitch structure is that is has been found to have a relatively higherspeed of operation than known switch structures of the same generaltype. This advantage is particularly important when such a switchstructure is employed to actuate the operation of an associatedprotective device, such as a circuit breaker.

Since numerous changes may be made in the abovedescribed apparatus anddifferent embodiments of the invention may be made without departingfrom the spirit and scope thereof, it is intended that all the mattercontained in the foregoing description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

We claim as our invention:

1. A switch comprising separable stationary and movable contacts, arotatable shaft for actuating the movement of said movable contactsbetween first and second operating positions corresponding to first andsecond angular positions, respectively, of said shaft, means for biasingthe shaft toward said first angular position, a lever arm mounted onsaid shaft for rotation therewith, a magnetic armature mounted on saidlever arm for movement therewith, a stationary magnetic structureincluding a permanent magnetic member disposed adjacent to said shaft,said magnetic armature being disposed to engage said stationary magneticstructure in the second angular position of said shaft with saidpermanent magnet member providing magnetic fiux which passes throughsaid magnetic armature to normally latch said shaft in the secondangular position against the influence of said biasing means, andelectromagnetic means disposed on said stationary magnetic structure andenergizable to provide magnetic flux which opposes the magnetic fluxfrom said permanent magnet member, which passes through said armature,to thereby release said armature and said shaft and to permit said shaftto be actuated to said first angular position by said biasing means. g

2. The combination as claimed in claim 1 wherein an additional rotatableshaft is provided having a handle mounted thereon for rotationtherewith, and means is provided for coupling said additional shaft tothe first-mentioned shaft for rotation therewith for a direction ofrotation toward said second angular position and with a predeterminedamount of rotary lost motion between said shafts for direction ofrotation.

3. The combination as claimed in claim 2 wherein a stop means isprovided adjacent said additional shaft .to prevent rotation of saidadditional shaft in said opposite direction of the opposite rotationbeyond said predetermined amount of rotary lost momeans of said handlein said opposite direction of rotation within the limits of saidpredetermined amount of rotary lost motion, and then released.

6. A switch comprising a generally cylindrical stator housing, a firstshaft rotatably disposed in the housing, a rotor rotatable with thefirst shaft, one or more movable contacts mounted on the rotor, aplurality of spaced stationary contacts mounted on the stator housing,said one or more movable contacts being actuable between first andsecond operating positions with respect to said stationary contacts uponrotation of said shaft between corresponding first and second angularpositions, means disposed adjacent to said shaft for releasably biasingsaid shaft substantially in the first of said angular positions, asecond shaft having a handle thereon for movement therewith rotatablydisposed adjacent to said first shaft, means for coupling said firstshaft to said second shaft for rotation therewith in a direction ofrotation toward said second angular position and with a predeterminedamount of rotary lost motion between said shafts in the other directionof rotation, a lever arm mounted on said first shaft for rotationtherewith, a magnetic armature mounted on said lever arm for movementtherewith, a stationary magnetic structure including a permanent magnetmember disposed adjacent to said first shaft, said magnetic armaturebeing disposed to engage said stationary magnetic structure in thesecond angular position of said first shaft with said permanent magnetmember providing magnetic flux which passes through said magneticarmature to magnetically latch said first shaft in the second angularposition against the influence of said biasing means, andelectromagnetic means disposed on said stationary magnetic structure andenergizable to provide a magnetic flux which opposes the magnetic fiuxfrom said permanent magnet member which passes through said magneticarmature, to thereby release said armature and said first shaft and topermit said first shaft to be actuated to said first angular position bysaid biasing means.

said second shaft is rotated by means of said handle in said otherdirection of rotation within the limits of said predetermined amount ofrotary lost motion and then released.

9. The combination as claimed in claim 6 wherein a handle is coupled tosaid shaft with a predetermined amount of rotary lost motion betweensaid handle and said shaft for a direction of rotation of said shafttoward the first angular position.

1. A switch comprising separable stationary and movable contacts, arotatable shaft for actuating the movement of said movable contactsbetween first and second operating positions corresponding to first andsecond aNgular positions, respectively, of said shaft, means for biasingthe shaft toward said first angular position, a lever arm mounted onsaid shaft for rotation therewith, a magnetic armature mounted on saidlever arm for movement therewith, a stationary magnetic structureincluding a permanent magnetic member disposed adjacent to said shaft,said magnetic armature being disposed to engage said stationary magneticstructure in the second angular position of said shaft with saidpermanent magnet member providing magnetic flux which passes throughsaid magnetic armature to normally latch said shaft in the secondangular position against the influence of said biasing means, andelectromagnetic means disposed on said stationary magnetic structure andenergizable to provide magnetic flux which opposes the magnetic fluxfrom said permanent magnet member, which passes through said armature,to thereby release said armature and said shaft and to permit said shaftto be actuated to said first angular position by said biasing means. 2.The combination as claimed in claim 1 wherein an additional rotatableshaft is provided having a handle mounted thereon for rotationtherewith, and means is provided for coupling said additional shaft tothe first-mentioned shaft for rotation therewith for a direction ofrotation toward said second angular position and with a predeterminedamount of rotary lost motion between said shafts for the oppositedirection of rotation.
 3. The combination as claimed in claim 2 whereina stop means is provided adjacent said additional shaft to preventrotation of said additional shaft in said opposite direction of rotationbeyond said predetermined amount of rotary lost motion.
 4. Thecombination as claimed in claim 2 wherein a spring biasing means isprovided for returning said additional shaft to a predetermined positionwhen said additional shaft is actuated in said opposite direction ofrotation.
 5. The combination as claimed in claim 2 wherein a springbiasing means is provided adjacent said additional shaft for returningsaid additional shaft to an angular position corresponding to saidsecond angular position of the first-mentioned shaft when saidadditional shaft is manually rotated by means of said handle in saidopposite direction of rotation within the limits of said predeterminedamount of rotary lost motion, and then released.
 6. A switch comprisinga generally cylindrical stator housing, a first shaft rotatably disposedin the housing, a rotor rotatable with the first shaft, one or moremovable contacts mounted on the rotor, a plurality of spaced stationarycontacts mounted on the stator housing, said one or more movablecontacts being actuable between first and second operating positionswith respect to said stationary contacts upon rotation of said shaftbetween corresponding first and second angular positions, means disposedadjacent to said shaft for releasably biasing said shaft substantiallyin the first of said angular positions, a second shaft having a handlethereon for movement therewith rotatably disposed adjacent to said firstshaft, means for coupling said first shaft to said second shaft forrotation therewith in a direction of rotation toward said second angularposition and with a predetermined amount of rotary lost motion betweensaid shafts in the other direction of rotation, a lever arm mounted onsaid first shaft for rotation therewith, a magnetic armature mounted onsaid lever arm for movement therewith, a stationary magnetic structureincluding a permanent magnet member disposed adjacent to said firstshaft, said magnetic armature being disposed to engage said stationarymagnetic structure in the second angular position of said first shaftwith said permanent magnet member providing magnetic flux which passesthrough said magnetic armature to magnetically latch said first shaft inthe second angular position against the influence of said biasing means,and electromagnetic means disposed on said stationary magnetic structureand energizable to provide a magnetic flux which opposes the magneticflux from said permanent magnet member which passes through saidmagnetic armature, to thereby release said armature and said first shaftand to permit said first shaft to be actuated to said first angularposition by said biasing means.
 7. The combination as claimed in claim 6wherein a stop means is disposed adjacent to said second shaft toprevent said second shaft from rotating in said other direction ofrotation beyond said predetermined amount of rotary lost motion.
 8. Thecombination as claimed in claim 6 wherein a spring biasing means isprovided adjacent said second shaft for returning said second shaft toan angular position corresponding to the second angular position of saidsecond shaft when said second shaft is rotated by means of said handlein said other direction of rotation within the limits of saidpredetermined amount of rotary lost motion and then released.
 9. Thecombination as claimed in claim 6 wherein a handle is coupled to saidshaft with a predetermined amount of rotary lost motion between saidhandle and said shaft for a direction of rotation of said shaft towardthe first angular position.